1. Field of the Invention
The present invention relates to a method for manufacturing a flat type display device and a flat type display device manufactured by the same, and particularly to a sealant applying method, which is used for sealing a liquid crystal material within a liquid crystal panel.
2. Description of the Prior Art
Conventionally, the following methods as a method for sealing a liquid crystal within the inside of a liquid crystal panel have been known. That is, in one case, a sealant is applied to one substrate to form an closed loop thereon and the one substrate is adhered to the other substrate via the closed-loop-shaped sealant, and then, a liquid crystal material is sucked into a space between the one and other substrates via a gap formed in via the closed-loop-shaped sealant. In another case, a sealant is applied to one substrate to form an closed loop thereon and a liquid crystal material is dropped within the closed loop on the one substrate, and then, the other substrate is adhered to the one substrate having the liquid crystal material dropped thereon via the closed-loop-shaped sealant.
According to the one method in which a liquid crystal is sucked into a space between the one and other substrates, it is necessary to keep a part of the sealant open so that the part serves as an inlet through which a liquid crystal material is guided into the space between the two substrates. According to the other method in which a liquid crystal material is dropped on one substrate, as shown in a plan view of FIG. 1, a sealant 4 is coated on a substrate 2 so as to completely surround a periphery of a display region 8. Therefore, when using a nozzle to coat a sealant, the sealant 4 is coated such that one end portion of the sealant 4 overlaps the other end portion thereof at around a start point where the sealant begins traveling on the substrate and a termination point where the sealant terminates traveling on the substrate, as shown in FIGS. 2A and 2B. Note that FIG. 2A is an enlarged plan view of an overlapped portion 10 in a situation where the sealant is coated on the substrate 2 such that one end portion of the sealant overlaps the other end portion thereof and the substrate 2 and the other substrate are disposed facing each other before pressing the two substrates to adhere to each other. FIG. 2B is a sectional view of the overlapped portion 10 cut along the line X-Xxe2x80x2 of FIG. 2A.
However, as described above, when the sealant 4 is coated on the substrate 2 such that one end portion of the sealant overlaps the other end thereof and the substrate 2 and the other substrate are pressed against each other, the overlapped portion 10 becomes wider than other portion of the sealant in which the sealant is not made overlapped each other while intruding into the display region 8, as shown in FIG. 1, thereby causing various problems. To prevent the sealant, i.e., an expanded-overlapped portion 20, from intruding the display region, the overlapped portion 10 has to previously be formed apart a long distance from the display region 8, thereby forcing a manufacturer to keep an additional space for a sealant.
An object of this invention is to provide a method for manufacturing a flat type display device to prevent a sealant from intruding into a display region of the device and remove an undesired space from the device by reducing spacing between the sealant and the display region. Another object of this invention is to provide a flat type display device manufactured by the above-described method.
The method for manufacturing a flat type display device according to the present invention is constructed such that a sealant is coated on at least one of two opposing substrates so as to surround a display region in such a manner that a start point and a termination point of the sealant are displaced from the display region toward a periphery of the at least one of two opposing substrates, the start point and termination point being defined such that coating of the sealant begins at the start point and terminates at the termination point, and the two opposing substrates are adhered to each other to form a closed loop consisting of the sealant with a recess formed in an inner periphery of the closed loop.
The method for manufacturing a flat type display device has two application forms as follows.
First, the sealant is coated to cross over a part of the sealant before the termination point, the part being located just next to the start point.
Secondly, the start point and the termination point are apart from each other before the step for adhering the two opposing substrates to each other and the start point and the termination point of the sealant melt in each other in the step for adhering the two opposing substrates to each other.
Therefore, according to a method for manufacturing a flat type display device constructed in accordance with the present invention, when coating a sealant on a periphery of a display region of a flat type display device, the sealant is coated such that the sealant is formed traveling apart gradually from the display region toward start and termination points of the sealant while overlapping a part thereof outside the closed loop portion and therefore, even when the two substrates are adhered to each other to resultantly widen the width of the sealant, the sealant never intrudes into the display region.